The objective of the PLATO project is the development and realisation of key building blocks for high density, re-configurable interconnections for optical or hybrid electro-optical systems. The envisaged application of the project is the interconnection mesh within large broad band switching systems. The proposed interconnection concept has to handle a massive number of high bitrate links inside a rack and between racks over distances up to hundreds of metres. The mesh of point to point optical interconnections developed in the project will be reconfigurable in an easy and cost effective way, reducing the extensive recabling during system upgrades. The approach will be compatible with existing equipment practice for high bitrate electrical interconnections.
By the end of the project key building blocks for high density, reconfigurable interconnections for optical or hybrid electro-optical systems will be available:
reconfigurable optical back panels
parallel electro-optical modules
multifibre (16 fibres) SM optical back panel connector
These building blocks will be integrated in a system demonstrator at the National Host.
In order to offer broad band services to a large population of users, large ATM systems are required, in which optical interconnections become a necessity. Since there will be a gradual introduction of these systems, the telecom operators will start with the installation of small upgradable broad band switching systems. The developed concept will allow the operator to upgrade step by step the installed system, paving "information highways" and accelerating the introduction of new interactive services.
In addition the building blocks are generic and can be used in a variety of systems where parallel optical interconnections, point to point interconnections, fibre handling, massive cable volumes or recabling becomes an issue. The interconnection concept can be used in the access network, transmission networks and the distribution area of the operator.
Main contributions to the programme objectives:
Developed an advanced optical interconnection concept for large ATM networks
Contribution to the programme
Technology for upgradable broadband switches up to the level of large public networks
One of the key elements is an electro-optical back panel made by discrete wiring of single mode fibres, providing the required point to point links. Passive functions of signal distribution and reshuffling of signal paths will be handled by small adapters or reconfiguration switches, which can be attached to the back panel (or boards) by an electro-optical socket to be developed. On the ATM boards (or on special application cards) parallel transmit or receive modules are placed. The optical interface from the modules to the back panel and from back panel to fibre ribbon cables will be realised by multifibre connectors. For the optical interface of the electro-optical socket beam expansion techniques and mirrors will be used. Based on this experience, the feasibility of an orthogonal fibre array connector will be studied. The performance of the optical links will be evaluated at bitrates up to 2.5 Gbit/s per channel; a system specific demonstrator will be built with links of 622 Mbit/s per channel.
Key Building blocks
The different building blocks are integrated in the architecture of a broad band switching system for the realisation of the optical interconnection mesh.
Optical back panels enable the usage of fibre ribbons and parallel electro-optical modules for point to point interconnections by shuffling the optical links
Electro-optical sockets are integrated on the rigid part of the electro-optical back panel to make the interconnection mesh reconfigurable.
Laminate based building blocks are integrated in the electro-optical socket to provide the electro-optical back panel with additional functionality
Parallel electro-optical modules are used for the realisation of the 622 Mbit/s bi-directional interfaces within the envisaged application.
A multifibre (16 fibres) SM optical back panel connector is used for interconnecting the optical back panels, the ribbon fibres and the electro-optical modules.
Summary of Trial
Since most of the building blocks are generic, they can be used in a variety of optical or hybrid electro-optical systems. By the end of the project the building blocks will be integrated in a system demonstrator at the National Host, illustrating the capabilities of the interconnection concept within a broad band switching system.
optical back panel with single mode fibres
multifibre back panel connectors for single mode fibres
passive adapters for reconfiguration and micromachined fibre switches
multifibre E/O modules (4x622 Mbit/s) for system application
Funding SchemeCSC - Cost-sharing contracts